Aporte original por: tcagle53 ,
From what I've been able to see on line in miata forums these older miatas are non interference designs that won't eat the valves when the belt turns loose. Removing the valve cover and manually turning the cams can confirm this... If any valves show massive clearances at any point of rotation it is of course indicative of bent valve stems. Naturally if you encounter serious resistance trying to turn a cam you should refrain from forcing it.